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Summary: Two different tactics are currently being utilized to control rabies in foxes, skunks and raccoons in Ontario, Canada. The first tactic, which involves live-capturing with cage-traps and vaccinating by intramuscular injection, was successful in immunizing 54%-72% of the skunk and raccoon populations in a 60 km2 area of Toronto, Ontario. This area has been free of rabies for two-anda-half years. The second tactic, involving the distribution of baits containing modified live-virus (ERA) rabies vaccine, was implemented to control rabies in foxes in both urban and rural areas of Ontario. In Toronto, 50% and 63% of the foxes were vaccinated during 1989 and 1990, respectively. Over the same period, 45% and 61% of the foxes in a 30,000 km2 area of south-eastern Ontario were immunized. Rabies is declining in both of these areas. A contingency plan has been devised to control an epizootic of raccoon rabies which is threatening to invade Ontario from the United States of America.

Climate is an important control on biomass burning, but the sensitivity of fire to changes in temperature and moisture balance has not been quantified. We analyze sedimentary charcoal records to show that the changes in fire regime over the past 21,000 yrs are predictable from changes in regional climates. Analyses of paleo- fire data show that fire increases monotonically with changes in temperature and peaks at intermediate moisture levels, and that temperature is quantitatively the most important driver of changes in biomass burning over the past 21,000 yrs. Given that a similar relationship between climate drivers and fire emerges from analyses of the interannual variability in biomass burning shown by remote-sensing observations of month-by-month burnt area between 1996 and 2008, our results signal a serious cause for concern in the face of continuing global warming.